Is this mold or pellicle?

[Garrett]

I haves Belgian tripel that fully fermented out then racked to secondary with6lbs of puréed guava. It's been about two weeks and I just noticed today there is two formations on top of the beer. What do you think it is and what should I do about it? This is the first time in 2 years of brewing I have had something like this happen, so very unsure what it is. The abv is 9%.

 

[runningweird]

well, does it matter? I can't identify the infection on sight, you would need a culture to do that. It is infected, you can probably save it.

rack out from underneath it and bottle/keg - that's your best bet.

 

[Yooper]

Boy, that doesn't look good. There is a ton of headspace in there, with plenty of oxygen contact, so it could be mold. But it could be something else too. It's hard to say.

 

[runningweird]

yeah yoop, but wouldn't that much time have seen the use/ejection of the oxygen through the airlock during the fermentation of the guava?

 

[runningweird]

how did you sanitize your fruit before putting it in the carboy?

 

[Garrett]

how did you sanitize your fruit before putting it in the carboy?

From the research I did, I figured racking on top of the guava with a 9%abv beer would be enough to keep it sanitized, plus it did referment creating a lot of c02 activity which caused airlock activity for days.

 

[opus345]

I haven't done this yet, but I'm trying to be read up on these events to hopefully avoid em. I'm betting without sanitizing the fruit you introduced a wild yeast into the beer. A number of folks on HBT have stated that a good vodka soak can help sanitize.

 

[Yooper]

yeah yoop, but wouldn't that much time have seen the use/ejection of the oxygen through the airlock during the fermentation of the guava?

No. Remember that even in an active fermentation it's never 100% co2, and in a "secondary" it's far less. With that much headspace (and the Ideal Gas Law), an infection or mold growth wouldn't be unexpected. I'm a winemaker, and that's one of the things we always do in secondary- an appropriate sized carboy and appropriate topping up. Short term, it's usually not an issue for beer. Unless it is.

 

[Garrett]

Well, I went ahead and bottled it up this morning. It was bit tart but that could be from the guava. Ill give it a try in 3-4 weeks and see how it is. either way it was an experiment, that I know how to properly execute next time! Thats what homebrewing is all about right?

 

[WoodlandBrew]

Canned fruit you could get away with. Frozen fruit probably. Fresh fruit probably not. Here is how I pasteurize fruit:
http://woodlandbrew.blogspot.com/2012/11/fruit-easy-way.html

 

[Garrett]

Canned fruit you could get away with. Frozen fruit probably. Fresh fruit probably not. Here is how I pasteurize fruit:
http://woodlandbrew.blogspot.com/2012/11/fruit-easy-way.html

Thanks for the tip! I will definitely try this on the next brew!